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arXiv · hep-th/0011107

Boundary Rings and N=2 Coset Models

W. Lerche·J. Walcher
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Abstract

We investigate boundary states of N=2 coset models based on Grassmannians Gr(n,n+k), and find that the underlying intersection geometry is given by the fusion ring of U(n). This is isomorphic to the quantum cohomology ring of Gr(n,n+k+1), and thus can be encoded in a ``boundary'' superpotential whose critical points correspond to the boundary states. In this way the intersection properties can be represented in terms of a soliton graph that forms a generalized, Z_{n+k+1} symmetric McKay quiver. We investigate the spectrum of bound states and find that the rational boundary CFT produces only a small subset of the possible quiver representations.

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W. Lerche, J. Walcher. 2000-12-23. Boundary Rings and N=2 Coset Models. https://doi.org/10.1016/s0550-3213(02)00019-6

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